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51.
Spatial thinking and spatial knowledge generation in decision-making are still not mature fields of study in planning research, despite these being crucial elements in addressing the issues of the twenty-first-century city. This article contributes to their understanding by exploring their interrelationships with spatial data usage. Through storylines, it analyzes the arguments that planning practitioners offer in support of infrastructure-led decisions in Arequipa (Peru), before and after spatial data usage. The article concludes that spatial data usage improve spatial thinking to different extents, yet suggests aligning spatial data generation and the inclusion of GIS-based spatial analyses with the spatial knowledge needed by routine planning practice.  相似文献   
52.
高速铁路具有高度集成、高精度的技术特点,运营过程中经受列车质量、速度、密度等多种因素影响,地理位置因素往往是影响铁路设备状态演变的决定性因素。采用网格化管理技术可将空间上连续分布的管理对象划分成较小的单元网格,有利于从空间位置角度研究管理对象状态的变化规律。随着信息系统技术、大数据技术的迅猛发展,基于位置而不是基于专业更符合高速铁路的管理需求,网格化管理技术给高速铁路管理带来了新的视角。  相似文献   
53.
在反倾销诉讼中,掌握度的规则,抓住关节点,对提升会计应诉水平具有重要意义。从会计应诉的实践要求来看,着重从两个方面把握住度的要求:一是把握会计应诉决策的度,使会计应诉决策建立在科学的基础上;二是把握会计应诉各环节的度,提升会计应诉的针对性和有效性。  相似文献   
54.
Neighbourhood planning (NP) as enabled by the 2011 Localism Act in England has precipitated a considerable literature discussing its potential, limitations and likely shortcomings referenced against government rhetoric and the reporting of initial experiences of the process. This paper provides an overview of the current literature on neighbourhood planning and sets out how it has been received and practised across England drawing on empirical evidence. The extent of take-up and the experience of those involved in the first five years of neighbourhood planning is used to consider how community-led planning may be designed and used following operational principles of inclusivity, capacity-building and adding value.  相似文献   
55.
园林景观规划设计与地域文化   总被引:1,自引:0,他引:1  
地域文化的缺失导致园林景观规划设计及其实施效果呈现雷同的趋势,通过提出规划设计中地域文化的范畴和意义,强调了体现地域文化在规划设计中的重要性。借助三个实际的规划设计案例从宏观角度提出规划概念应与地域自然特点、人文特点等要素有机结合,从而从微观角度提出设计可采用保留、抽取、融合、再现等手法来体现地域文化。此外,在规划设计中运用地域文化应该注意契合性、创新性、烂漫性及可实施性等的几个方面的问题。  相似文献   
56.
In this paper, we first introduces a tree model without degree boundedness restriction namely generalized controlled tree T, which is an extension of some known tree models, such as homogeneous tree model, uniformly bounded degree tree model, controlled tree model, etc. Then some limit properties including strong law of large numbers for generalized controlled tree-indexed non homogeneous Markov chain are obtained. Finally, we establish some entropy density properties, monotonicity of conditional entropy, and entropy properties for generalized controlled tree-indexed Markov chains.  相似文献   
57.
Conditional value-at-risk (CVaR) model is a kind of financial risk measure that is extensively supported and accepted by international financial community. Its optimized form can be regarded as an optimized certainty equivalent (OCE) risk measurement. In this paper, we mainly discuss and analyze the strong laws of large numbers and the convergence rate of OCE's estimator under α-mixing sequences. The result shows that the almost sure convergence rate of CVaR estimator is given by the results of OCE estimator. Its convergence rate is inversely proportional to the square root of the sample size under certain conditions. Its effectiveness is verified by simulation experiments for two classical α-mixing sequences.  相似文献   
58.
In this paper, we analyze the emerging retail practice of carrying a combined product assortment consisting of both regular “standard” products and more fashionable and short-lived “special” products. The purpose of this practice is to increase store traffic by attracting heterogeneous classes of customers, which drives up sales of standard products due to the potential cross-selling effect. Customers who are primarily attracted by special products will also buy some standard products. In this context, we analyze three decisions that are crucial for a retailer׳s commercial success: the product assortment, the inventory levels and the pricing. We propose an optimization model and an iterative heuristic to analyze the trade-offs between the combined product assortment, the inventory level and the price per product when there is limited shelf space. Using numerical experiments, we show that our heuristic can be trusted and that its accuracy improves when the number of products increases. Our findings indicate that to attract more customers for standard products, a retailer may benefit from carrying low priced special products which, if considered in isolation, would be non-profitable. As the cross-selling effect decreases, a retailer should focus more on the standard assortment by increasing its size and decreasing the prices. However, introducing special products and ignoring the cross-selling effect may decrease a retailer׳s profitability. We show that the introduction of special products involves more than just choosing the right specials for non-loyal customers but impacts the global assortment planning, the standard products and the products pricing.  相似文献   
59.
Tactical production-distribution planning models have attracted a great deal of attention in the past decades. In these models, production and distribution decisions are considered simultaneously such that the combined plans are more advantageous than the plans resolved in a hierarchical planning process. We consider a two-stage production process, where in the first stage raw materials are transformed into continuous resources that feed the discrete production of end products in the second stage. Moreover, the setup times and costs of resources depend on the sequence in which they are processed in the first stage. The minimum scheduling unit is the product family which consists of products sharing common resources and manufacturing processes. Based on different mathematical modelling approaches to the production in the first stage, we develop a sequence-oriented formulation and a product-oriented formulation, and propose decomposition-based heuristics to solve this problem efficiently. By considering these dependencies arising in practical production processes, our model can be applied to various industrial cases, such as the beverage industry or the steel industry. Computation tests on instances from an industrial application are provided at the end of the paper.  相似文献   
60.
Pitman closeness of both the upper and lower k-record statistics to the population quantiles of a location–scale family of distributions is studied. For the population median, the Pitman-closest k-record is also determined. In the case of symmetric distributions, the Pitman closeness probabilities of k-record statistics are shown to be distribution-free, and explicit expressions are also derived for these probabilities. Exact expressions are derived for the required probabilities for uniform and exponential distributions. Numerical results are given for these families and also the Pitman-closest k-record is determined.  相似文献   
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